It has been known that "color fogging" phenomenon is caused in color photographic sensitive materials which contain a compound (referred to as a dye releasing redox, or DRR, compound) which releases a diffusible dye by a redox reaction upon development of a silver halide photographic sensitive material, and are developed with a black-white developing agent such as phenidone, etc., or in color photographic sensitive materials which contain couplers and are developed with a color developing agent, and it has been well known that various oxidized developing agent scavengers are used for preventing such a phenomenon.
In the case of color photography, the above-described oxidized developing agent scavenger is incorporated in intermediate layers in order to obtain good color separation or in silver halide emulsion layers or layers containing a dye image donator (for example, the combination of a dye releasing redox compound and a coupler) combined with the silver halide emulsion layer in order to obtain a reduced minimum density.
It has been well known heretofore to use various substituted hydroquinones as an oxidized developing agent scavenger. For example, use of mono-substituted alkylhydroquinones is described in U.S. Pat. Nos. 2,360,290, 2,418,613, 2,403,721 and 3,960,570. Further, methods using mono-branched alkylhydroquinones are described in U.S. Pat. No. 3,700,453, German Patent Application (OLS) No. 2,149,789, and Japanese Patent Application (OPI) Nos. 156438/75 and 106329/74 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application"). Use of disubstituted alkylhydroquinones is described in U.S. Pat. Nos. 2,728,659, 2,732,300 and 3,243,294, British Pat. No. 752,146 and Chemical Abstracts, Vol. 56, 6367h, and use of a di-branched alkylhydroquinones is described in U.S. Pat. Nos. 3,700,453, 2,732,300 and 3,243,294, Chemical Abstracts, Vol. 56, 6367h, Japanese Patent Application (OPI) Nos. 156438/75, 9528/78, 29637/79 and Japanese Patent Publication No. 21249/75.
In addition, use of substituted hydroquinones as the oxidized developing agent scavenger has been described in U.S. Pat. Nos. 2,701,197, 2,710,801, and 2,704,713.
Furthermore, use of sulfonamidophenols as the oxidized developing agent scavenger has been described in Research Disclosure, 15162 (No. 151, 1976) page 83 and Japanese Patent Application (OPI) No. 72158/80.
However, since the above-described known compounds do not completely satisfy all desired properties for the oxidized developing agent scavenger in color photography, particularly, in a color diffusion transfer process, it has been desired to discover more suitable compounds. These desired properties are described in detail below.
(1) The oxidized developing agent scavenger is a compound capable of suitably reacting with a oxidized developing agent formed by development of silver halide. For example, a compound to be incorporated in an intermediate layer is incorporated in the intermediate layer located between a silver halide emulsion layer and a layer containing a dye releasing redox compound (or a coupler) which is not associated with the emulsion layer in order to prevent reacting the oxidized developing agent formed by development of silver halide with the dye releasing redox compound (or the coupler) which is not combined with said silver halide. "Associated" as used herein refers a compound being present in the same, or an adjacent layer, with respect to a particular silver halide emulsion layer. In this case, it is necessary that the compound reacts with the oxidized developing agent to "capture" it to the extent that diffusion of the oxidized developing agent into the layer containing the dye releasing redox compound (or coupler) which is not associated is substantially nothing.
If the reactivity of the compound with the oxidized developing agent is too high, the compound interferes with the reaction of the oxidized developing agent formed by development of silver halide with the dye releasing redox compound associated with said silver halide to deteriorate the maximum dye image density. Accordingly, it is desired to have a suitable reactivity.
(2) Film thickness of the photosensitive material can be minimized when the oxidized developing agent scavenger is added to the photosensitive material. In the case of a color diffusion process, it is often necessary that a dye released from a dye releasing redox compound passes through the layer containing the oxidized developing agent scavenger. The film thickness of the layer containing the oxidized developing agent scavenger can be decreased as the amount of the oxidized developing agent scavenger and other materials required for addition of the oxidized developing agent scavenger (e.g., gelatin and high boiling point solvents). Consequently, the time necessary for passage of the released dye through this layer is shortened, and sharpness of transfer images is improved. In an instant color diffusion transfer process wherein it is required to complete image formation in as short a time as possible, it is particularly important to minimize the film thickness.
(3) Adverse influences upon the silver developing property in the silver halide emulsion are lessened when the oxidized developing agent scavenger is added to the photosensitive material. Particularly in the case of a developing process in which a positive image is formed directly by use of an inner latent image type silver halide emulsion, the oxidized developing agent scavenger in the silver halide emulsion layer or in the layer adjacent to the silver halide emulsion layer often has adverse influences upon the silver development property. Accordingly, it is desirable to use a compound having less adverse influences.
(4) The oxidized developing agent scavenger should not reduce a diffusible dye or a diffusible dye precursor to change its hue when subjected to high pH development processing. Particularly, some dialkylhydroquinone compounds in oxidized developing agent scavengers sometimes cause a change of the hue of the compounds having a dye constitutional residue containing a reducible group (for example, a nitro group) in the dye constitutional part. Since such a change of the hue has a significant adverse influence upon color reproduction, it is very important from this point of view to select an oxidized developing agent scavenger that does not adversely affect the hue of a compound having a dye constitutional residue containing a reducible group in its dye constitutional part (for example, a monoazo naphthol dye having a nitro group).
(5) The oxidized developing agent scavenger should not produce photographically adverse effects caused by migration of the scavenger into each layer of the color photographic sensitive material. It is necessary that such an adverse effect is not substantially produced before, during, or after the processing of the color photographic sensitive material.
(6) The oxidized developing agent scavenger should be relatively independent of the processing temperature during development processing (i.e., it should have a broad latitude for the development processing temperature). This is particularly necessary for a color diffusion transfer process, which must have a high photographic sensitivity, a sufficiently large maximum density, a sufficiently low minimum density, and a suitable gradation, even if the processing temperature changes.
(7) The oxidized developing agent scavenger should neither cause deterioration of quality of the coated material because of precipitation of crystals during or after application thereof, nor produce colored by-products, because it does not cause an oxidation reaction during the application operation or processing.
Thus a continuing need has existed for compounds satisfying the above-described requirements for an oxidized developing agent scavenger.